Water-soluble azo dyestuffs



Patented Apr. 11, 1939 UNITED STATES PATENT OFFICE 2,154,186 WATER -SOLUBLE AZO DYESTUFFS No Drawing.

Application June 5, 1936, Serial No. 83,792. In Germany June 29, 1935 3 Claims. (or 266-163) The present invention relates to new watersoluble azo dyestuffs, more particularly it relates to azo dyestuffs which are characterized by containing in a diazotization component a sulfofluoride group (SOzF) andwhich are constituted in. such a manner that at least one sulfonic acid group is present in the dyestuff molecule.

Our new dyestuffs which may be represented by the following general formula: R-N=N-R1 I 01F wherein R stands for an aromatic radical, R1 stands for the radical of an azo dyestufi coupling component and n stands for a whole number, are

obtainable by diazotizing an aminoaryl-sulfofiuoride and coupling with one of the usual coupling components generally in the manufacture of azodyestufis, for example: pyrazolone sulfonic acids, hydroxy and aminonaphthalene sulfonic acids, aminonaphthol sulfonic acids, their acyl derivatives, and others; thereby the components are selected in sucha'. manner that at least one sulfonic acid group is present inthe dyestuff molecule.

Our new dyestuffs are in form of their alkali metal salts watersoluble powders yielding; depending upon the specific components used in their manufacture, on fibers, such as wool, various shades. The shades obtained are in general very clear and of good fastness to light, and particularly they are distinguished in cases, besides their being even, by good fastr'ies's" to washing. y

The invention is illustrated by the ion-swine examples, but is not restricted thereto.

Example 1 17.5 grams of fi-aminobenzenesulfofluoride (melting point 30 0., manufactured from 3-ami- 40 nobenzene-l-sulfonic acid by means of fluorosulfonic acid) are; diazotized in the usual manner, inthe presence of hydrochloric acid, with 6.9 grams of sodium nitrite: The dia'zosolutioii is purified from small impurities and added to a 45 solution of grams o-f 1-(4'-su1fophenyl)-3- methyl-5 pyrazolone and 5-2 grams of crystallizedsodium acetate'injl liter of water.

After coupling is" complete, the dyestufl, having in its free state the following formula:

isworked up according to methods. It ayes wool even yellow snaaes of good fastness to light and washing.

Example 2 17.5 grams of 3'-aminob-enzene-l-sulfofluoride are diazotized as'describd in Example 1. Then the diazo solution is added to a solution of 22.4 grams of Z-naphthol-B-sulfonic acid in sodium bicarbonate. Whencoupling is complete, the dyestufi, having in its free state the following formula:

scan is worked up according to known methods. e It dyes wool even orange shades, which are fast to washing and to light. u 7

On replacing the Z-naphthol-fi-sulfonic acid by an equivalent quantity of l-acetylamino-ii-naphtliolf llfi disulfonic acid, there obtained a dyestun dyeing" red shades of similar properties.

Example 3 175 grams of Z-aminobenZen'e-l-sulfofluorid emeiung pcmt 67 C.,- manufactured from Z-aminobenzene-l-sulfonicacid by means oi fluorosu'l fof-iic acid) are diazotized as indicated in Examare 1 maze compound is added to a s'olut'ion" of 28.8 of- 1-(2'-chloro'-'5'-sulfo)-3- methyl-B-pyrazolone and 52 grams of crystallized sodium acetate, and, after coupling is complete, the dyestufi, having in its free state the following formula:

H: is worked up according 'to known methods.

It dyes wb'ol everi g reeni'sh' yellow shades, which are fast to light and to w'ashing'.

20.3 grams of 2-amino-3.5-dimethylbenzene-1- sulfofluoride (melting point 105 0., manufactured from 2-amino-3.5-dimethylbenzene-l-sulfonic acid by means of fluorosulfonic acid) are dissolved in glacial acetic acid, grams of crude hydrochloric acid are added thereto as well as some ice, and diazotization is efiected as usual. The diazo compound is added to a solution of 28.1 grams of 2-acetylamino-8-naphtho1-6-sulfonic acid in 1 liter of water and 52 grams of crystallized sodium acetate. After coupling is complete, the dyestuff, having in its free state the following formula:

OH; OH

is worked up according to known methods.

It dyes wool even red shades, which are fast to washing and to light.

Example 20.3 grams of 2.4-dimethyl-S-aminobenzene-1- sulfofluoride (melting point 92 C., manufactured f r o m 2.4-dimethyl-5-aminobenzene-l-sulfonic acid by means of iiuorosulfonic acid) are diazotized as indicated in Example 4. The diazo compound is added to an ice cold solution of 1-(2'- sulfophenyl) -3-methyl -5-pyrazolone. After coupling is complete, the dyestuff, having in its free state the following formula:

s 05H CH1 is worked up according to known methods.

It dyes wool even greenish yellow shades, which are fast to washing and to light.

On replacing 1-(2'-sulfophenyl)-3-methyl-5- pyrazolone by 1-(3sulfophenyl)-3-methyl-5- pyrazolone or by LOP-sulfophenyl)-3-methyl-5- pyrazolone, dyestuifs of similar properties are obtained.

Example 6 18.9 grams of 2-methyl-4-aminobenzene-l-sulfofiuoride (melting point 65 C., manufactured from 2-methyl-4-amino-benzene-l-sulfonic acid by means of fluorosulfonic acid) are diazotized withsodium nitrite and hydrochloric acid as indicated in Example 1. The diazo compound is added to an ice cold solution of 22.4 grams of 1- naphthol-4-sulfonic acid, in the presence of sodium acetate, and, after coupling is complete, the dyestufi, having in its free state the following is worked up according to known methods.

It dyes wool even red shades, which are fast to washing and to light.

, On replacing the l-naphthol-i-sulfonic acid by the 3-methyl-5-pyrazolones from o, m or p-sul fanilic acid or from 2-chloraniline-5-sulfonic acid.

yellow dyestuffs with similar good properties are obtained.

On replacing the l-naphthol-l-sulfonic acid by the 2-acetylamino-8-naphthol-6-sulfonic acid, there is obtained a; dyestuff dyeing even red shades, which are fast to washing and to light.

' Example 7 18.9 grams of 2-methyl-5-aminobenzene-lsulfofiuoride are diazotized as indicated in Example 6. .Then the diazo compound is added to an ice cold solution of 23.7 grams of N-methyl-Z- naphthylamine-l-sulfonic acid in the presence of excess sodium acetate. After coupling is complete, the dyestufif, having in its free state the following formula:

H l q-CH: rosQm-mis worked up according to known methods.

.It dyes wool even yellowish red shades, which have also good fastness to washing and light.

We claim:

1. Watersoluble mono-azo dyestuffs of the general formula:

N=N--oHoo yielding on wool even yellow shades of good fastness to light and. washing.

3. The dyestuif having in its free state the following formula:

. p on Q yielding on wool even orange shades which are fasttowashing and to light.

'HUGO SCHWEITZER. OTTO BAYER. ,GERHARD SCHRADER. 

